EP1223811B1

EP1223811B1 - Morinda citrifolia oil

Info

Publication number: EP1223811B1
Application number: EP00961370A
Authority: EP
Inventors: John Wadsworth; Stephen Story
Original assignee: Tahitian Noni International Inc
Current assignee: Tahitian Noni International Inc
Priority date: 1999-08-27
Filing date: 2000-08-25
Publication date: 2009-01-14
Anticipated expiration: 2020-08-25
Also published as: DE60041412D1; MXPA02002145A; US6214351B1; JP2003508554A; EP1223811A1; AU7333100A; ATE420559T1; JP4198913B2; US6417157B1; WO2001015537A1; EP1223811A4

Abstract

An essential oil product obtained from the Indian mulberry (Morinda citrifolia) plant and the process of extracting and purifying the oil is disclosed. According to one embodiment, the seeds from the Indian mulberry fruit are dried, preferably to a moisture content less than 10%. The seeds are ground or shredded to facilitate the removal of natural occurring oil. The shredded or ground flakes are pressed to expel Morinda citrifolia oil. The remaining seed cake is then mixed with a food grade, non-polar extraction solvent such as hexane. The mixture is heated for a sufficient length of time to complete the extraction process. The extraction solvent is then evaporated from the mixture leaving the Morinda citrifolia oil. The oil is further refined, bleached, dried, and deodorized to remove free fatty acids and other unwanted components. An antioxidant can optionally be added to stabilize the oil for further processing or packaging.

Description

Field of the Invention

The present invention relates a process of extracting and purifying an essential oil product obtained from the Morinda citrifolia plant and to the oil itself.

Background of Invention

The Indian Mulberry plant, known scientifically as Morinda citrifolia L., is a shrub, or small or medium sized tree 3 to 10 meters high. It grows in tropical coastal regions around the world. The plant grows randomly in the wild, and it has been cultivated in plantations and small individual growing plots. The Indian mulberry plant has somewhat rounded branches and evergreen, opposite (or spuriously alternate), dark, glossy, wavy, prominently-veined leaves. The leaves are broadly elliptic to oblong, pointed at both ends, 10-30 cm in length and 5-15 cm wide.
The Indian mulberry flowers are small, white, 3 to 5 lobed, tubular, fragrant, and about 1.25 cm long. The flowers develop into compound fruits composed of many small drupes fused into an ovoid, ellipsoid or roundish, lumpy body, 5-10 cm long, 5-7 cm thick, with waxy, white or greenish-white or yellowish, semi-translucent skin. The fruit contains "eyes" on its surface, similar to a potato. The fruit is juicy, bitter, dull-yellow or yellowish-white, and contains numerous red-brown, hard, oblong-triangular, winged, 2-celled stones, each containing 4 seeds.
When fully ripe, the fruit has a pronounced odor like rancid cheese. Although the fruit has been eaten by several nationalities as food, the most common use of the Indian mulberry plant was as a red and yellow dye source. Recently, there has been an interest in the nutritional and health benefits of the Indian mulberry plant.
It would be a significant advancement in the art to provide the essential oil from the Indian mulberry plant and to provide a process for obtaining the essential oil from the Indian mulberry plant.
Various uses have been disclosed for substances derived from Morinda citrifolia. For example FR 2 673 639 describes uses of Morinda citrifolia as an insecticide. JP 8-217686 makes use of extract from the roots of Morinda citrifolia as a medicine to treat disease of the upper digestive tract. Levand & Larsen (Planta Medica, vol 36, no.2 1979, pp 186-187) disclose the results of analyses of a pulp extracted from the fruits of Morinda citrifolia.

Summary of the Invention

The present invention is directed to a process for extracting oil from Morinda citrifolia seeds comprising the steps of drying the seeds to a moisture content less than 10%; cracking, flaking, or grinding the seeds to form ground seeds; and pressing the processed seeds to expel Morinda citrifolia oil.
The invention is also directed to an essential oil extracted from Indian mulberry (Morinda citrifolia) seeds by the process set forth above.
The Indian mulberry oil typically includes a mixture of several different fatty acids as triglycerides, such as palmitic, stearic, oleic, and linoleic fatty acids, and other fatty acids present in lesser quantities.
The essential oil preferably includes an antioxidant to inhibit spoilage of the oil.
Conventional, food grade antioxidants are preferably used, including, but not limited to, tocopherol acetate (vitamin E acetate), propyl gallate, TBHQ (t-butyl hydroquinone), BHT (3,5-bis (t-butyl)-4-hydroxytoluene), and French maritime pine bark extract.
The process for extracting Indian mulberry oil from its seeds typically involves obtaining Indian mulberry seeds that are dried to a moisture content less than 10%, by weight, and preferably from 5% to 8%, by weight. The seeds are cracked, ground, flaked, shredded, or mechanically reduced in size, typically from 2 to 20 mm. As used herein, ground seeds include seeds that may be ground, cracked, flaked, shredded, or otherwise reduced in size. The ground seeds are then pressed in a mechanical press or screw press to expel some of the oil. The remaining seed cake is mixed with a nonpolar extraction solvent. The extraction solvent is preferable food-grade. One currently preferred nonpolar solvent is hexane.
Oil extraction with the nonpolar solvent preferably takes place at a temperature range between 30°C (80°F) and 90°C (200°F) and ranges from a time of 30 minutes up to 12 hours. It is presently preferred to complete the extraction step as quickly as possible. The nonpolar solvent is preferably removed from the extracted oil through flash evaporation.
The oil from the mechanical press and from the nonpolar solvent extraction may be combined or further refined separately. The refining process removes impurities from the oil. Caustic, water, and phosphoric acid can be added to the oil to precipitate impurities.
The precipitating agents and oil are mixed and heated to a temperature between 40°C (100°F)and 90°C (200°F), the currently preferred target temperature is between 75°C (170°F) and 80°C (180°F). The mixture is centrifuged to remove precipitated impurities that include, but are not limited to, insoluble gums, phosphatides, and free fatty acids.
The oil can optionally be further refined by bleaching and deodorizing. Bleaching involves the addition of one or more filtering agents to the oil. The oil is filtered through a mechanical filter to remove the filtering agents. Currently preferred filtering agents include diatomaceous earth (D.E.) and activated charcoal. Bleaching removes color bodies and soap materials generated during the refining process. Bleaching is preferably done at temperatures between 40°C (100°F)and 90°C (200°F).
The oil may or may not be vacuumed dried to remove any residual water. The oil is deodorized to remove volatile impurities. This involves steam distillation under a vacuum and at temperatures between 150°C (300°F) and 260°C (500°F). An antioxidant can be included with the extracted oil, as mentioned above.

Detailed Description of the Invention

The present invention is directed to an essential oil product obtained from the Indian mulberry (Morinda citrifolia) plant and to the process of extracting and purifying the oil. The oil is extracted from Indian mulberry seeds. The seeds from the Indian mulberry fruit are dried and then packed in large containers for storage and transport. The seeds can be processed immediately or they can be stored for a period of time, usually up to about one year.
The seeds are dried because residual water can contaminate the extraction solvent, which is oil based. Also the presence of water in the extraction process can cause oxidation of the oil. The rate of drying is preferably quick enough to be economical and slow enough to protect the oil from heat degradation. Drying usually takes from 10 to 100 days. The seeds are preferably dried in the sun or by a mechanical drier. The seeds are dried to a moisture content less than 10%, by weight, and preferably from about 5% to 8%, by weight. Conventional moisture detectors can be used to measure the moisture content of the seeds during and after the drying process.
The seeds are cracked, ground, flaked, shredded, or mechanically reduced in size in order to facilitate the removal of natural occurring oil. As mentioned above, the term ground seeds include seeds that are ground, cracked, flaked, shredded, or otherwise reduced in size. The seeds are preferably ground through a grinder or flaker with a grinder plate size between about 2 mm to 20 mm hole size. The seeds are optimally reduced to a size falling in this range. The ground seed size is important because it effects the yield and quality of the extracted oil. Too large a flake size decreases the yield. Too small a flake size leaves a lot of undesired seed components in the oil.
The ground seeds are preferably pressed in a mechanical press or screw press to expel some of the oil. The remaining seed cake is mixed with a nonpolar, food grade extraction solvent. Hexane is a currently preferred nonpolar solvent. The mixture of nonpolar solvent and seed cake is preferably heated to a temperature between 30°C (80°F) and 90°C (200°F) and for a time from about 30 minutes up to 12 hours. The nonpolar solvent mixes with the Indian mulberry oil remaining in the seeds and carries the oil out of the water based seed material matrix.
Indian mulberry oil pressed from the seeds and from the hexane extraction may be combined or further refined separately to remove impurities from the oil. Such unwanted impurities include, but are not limited to, insoluble gums, phosphatides, and free fatty acids. Caustic, water, and phosphoric acid are currently preferred precipitating agents that can be added to the oil to precipitate impurities. The oil and precipitating agent mixture is preferably heated to a temperature between 40°C (100°F)and 90°C (200°F), and more preferably heated to a temperature between 75°C (170°F) to 80°C (180°F). The mixture is preferably centrifuged to remove the precipitated impurities.
The oil may be optionally further refined by bleaching and deodorizing. Bleaching involves the addition of one or more filtering agents to the oil to remove color bodies and soap materials generated during the refining process. Currently preferred filtering agents include, but are not limited to diatomaceous earth (D.E.) and activated charcoal. The oil is filtered through a mechanical filter to remove the filtering agents. Bleaching is done at temperatures between 40°C (100°F) and 90°C (200°F). Residual water can be removed from the oil by vacuum drying.
The oil is preferably deodorized to remove volatile impurities. This involves steam distillation under a vacuum. Typical distillation temperatures range from 150°C (300°F) and 260°C (500°F).
An antioxidant can optionally be added to stabilize the oil for further processing or packaging. Suitable antioxidants include, but are not limited to, tocopherol acetate (vitamin E acetate), propyl gallate, TBHQ (t-butyl hydroquinone), BHT (3,5-bis (t-butyl)-4hydroxytoluene), French maritime pine bark extract. The Morinda citrifolia seed oil may be used in, but is not limited to massage oil, cosmetics, candles, and as a product by itself.
The fragrance of the oil ranges from a nutty, mellow fragrance to a slightly sharp chemical solvent fragrance. The extracted oil appearance is from a rich golden yellow to a brownish tan color with a clear transparency, preferably free of foreign material or particulates.
From an analysis of the Morinda citrifolia oil, the oil is mainly composed of fatty acids as triglycerides. The free fatty acid content typically ranges from 5 to 9 grams/100 grams oil. The peroxide value typically ranges from 3 to 6 MEQ/KG, and the vitamin E content typically ranges from 11 to 25 IU/100 gram. The approximate fatty acid composition of the oil is reported below in Table 1. Table 1

Fatty Acid Wt. %

Caprylic 0.5

Palmitic 8.4

Stearic 4.0

Oleic 13.8

Linoleic 66.8

Linolenic 0.2

Arachidic 0.5

Eicosenoic 0.2

Other fatty acids 5.6
The foregoing concentrations in the extracted oil can vary from one batch to another, but the variations generally do not exceed 10%, by weight.

Claims

A process for extracting oil from Morinda citrifolia seeds comprising the steps of:
drying the seeds to a moisture content less than 10%;

cracking, flaking, or grinding the seeds to form ground seeds; and

pressing the processed seeds to expel Morinda citrifolia oil.
A process as claimed in Claim 1, further comprising the steps of:
mixing the pressed, processed seeds with a nonpolar extraction solvent to allow Morinda citrifolia oil from the seeds to mix with the extraction solvent; and

heating the mixture of seeds and extraction solvent to a temperature between 30°C (80°F) and 90°C (200°F) to extract Morinda citrifolia oil from the seeds.
A process as claimed in Claim 2, wherein the mixture is heated for a period between 30 minutes and 12 hours.
A process as claimed in Claim 2 or Claim 3, further comprising the step of removing the extraction solvent from the extracted Morinda citrifolia oil by evaporation.
A process as claimed in any one of Claims 2 to 4, wherein the extraction solvent is a food-grade extraction solvent.
A process as claimed in any one of Claims 2 to 5, wherein the extraction solvent is hexane.
A process as claimed in any preceding claim, further comprising the step of removing impurities from the Morinda citrifolia oil.
A process as claimed in Claim 7, wherein the impurities are precipitated by addition of a precipitating agent and removed from the Morinda citrifolia oil by centrifuge.
A process as claimed in any preceding claim, further comprising the step of bleaching the Morinda citrifolia oil.
A process as claimed in Claim 9, wherein the step of bleaching the Morinda citrifolia oil comprises:
adding a filtering agent selected from diatomaceous earth (D.E.) and

activated charcoal to the Morinda citrifolia oil;

heating the mixture of filtering agent and Morinda citrifolia oil to a temperature between 40°C (100°F) and 90°C (200°F); and

removing the filter agent by mechanical filtration.
A process as claimed in any preceding claim, further comprising the step of deodorizing the Morinda citrifolia oil.
A process as claimed in any preceding claim, wherein the seeds are processed to a size between 2 mm to 20 mm.
A process as claimed in any preceding claim, further comprising the step of adding an antioxidant to the Morinda citrifolia oil.
A process as claimed in Claim 13, wherein the antioxidant is selected form tocopherol acetate (vitamin E acetate), propyl gallate, TBHQ (t-butyl hydroquinone), BHT (3,5-bis(t-butyl)-4-hydroxytoluene), and French maritime pine bark extract.
A process as claimed in any preceding claim, further comprising the step of removing volatile impurities by distilling the Morinda citrifolia oil.
A process as claimed in any preceding claim, further comprising the step of removing residual water by vacuum drying the Morinda citrifolia oil.
An essential oil comprising oil extracted from Morinda citrifolia seeds by the process of any preceding claim, wherein the extracted oil includes at least one of caprylic fatty acid; oleic fatty acid; and linoleic fatty acid;
An essential oil as claimed in Claim 17, further comprising an antioxidant.
An essential oil as claimed in Claim 18, wherein the antioxidant is selected from tocopherol acetate (vitamin E acetate), propyl gallate, TBHQ (t-butyl hydroquinone), BHT (3,5-bis(t-butyl)-4-hydroxytoluene), and French maritime pine bark extract.
An essential oil as claimed in any one of Claims 17 to 19, comprising palmitic, stearic, oleic, and linoleic fatty acids.
An essential oil as claimed in any one of Claims 17 to 20, wherein the oil extracted from Morinda citrifolia seeds further comprises at least one of:
palmitic fatty acid;,

stearic fatty acid;

linolenic fatty acid;

arachidic fatty acid; and

eicosenoic fatty acid.
An essential oil as claimed in any one of Claims 17 to 21, wherein the oil extracted from Morinda citrifolia seeds has a free fatty acid content ranging from 5 to 9 grams/100 grams oil.
An essential oil as claimed in any one of Claims 17 to 22, wherein the oil extracted from Morinda citrifolia seeds has a peroxide value ranging from 3 to 6 MEQ/KG.
An essential oil as claimed in any one of Claims 17 to 23, wherein the oil extracted from Morinda citrifolia seeds has a vitamin E content ranging from 11 to 25 IU/100 gram.
An essential oil as claimed in any one of Claims 16 to 24, wherein the oil extracted from Morinda citrifolia seeds comprises a mixture of caprylic, palmitic, stearic, oleic, linoleic, linolenic, arachidic, and eicosenoic fatty acid.
An essential oil as claimed in any one of Claims 16 to 25, wherein the oil extracted from Morinda citrifolia seeds comprises:
0.5 wt. % caprylic fatty acid;

8.4 wt. % palmitic fatty acid;

4.0 wt. % stearic fatty acid;

13.8.wt. % oleic fatty acid;

66.8 wt. % linoleic fatty acid;

0.2 wt. % linolenic fatty acid;

0.5 wt. % arachidic fatty acid; and

0.2 wt. % eicosenoic fatty acid;
wherein the foregoing concentrations can vary up to ±10%, by weight.
An essential oil as claimed in any one of Claims 16 to 26, wherein the extracted oil has a free fatty acid content ranging from 5 to 9 grams/100 grams oil; and an antioxidant.
An essential oil as claimed in Claim 27, wherein the antioxidant is selected from tocopherol acetate (vitamin E acetate), propyl gallate, TBHQ (t-butyl hydroquinone), BHT (3,5-bis(t-butyl)-4-hydroxytoluene), and French maritime pine bark extract.
An essential oil as claimed in any one of Claims 17 to 28, wherein the oil extracted from Morinda citrifolia seeds is bleached.
An essential oil as claimed in any one of Claims 17 to 29, wherein the oil extracted from Morinda citrifolia seeds is deodorized.
An essential oil as claimed in any one of Claims 17 to 30, wherein the oil extracted from Morinda citrifolia seeds has a peroxide value ranging from 3 to 6 MEQ/KG.
An essential oil as claimed in any one of Claims 17 to 31, wherein the oil extracted from Morinda citrifolia seeds has a vitamin E content ranging from 11 to 25 IU/100 gram.
A massage oil containing an essential oil as claimed in any one or more of Claims 17 to 32.
A cosmetic product containing an essential oil as claimed in any one or more of Claims 17 to 32.
A candle containing an essential oil as claimed in any one or more of Claims 17 to 32.